Variable 16Bit to 512Bit Hashing Algorithm

Sha16512.cs

using System;
using System.Security.Cryptography;
[Serializable]
public class Sha16512 : HashAlgorithm
{
    private int           _bitWidth;
    private SHA512Managed _hash = new SHA512Managed();
    public Sha16512(int bitWidth)
    {
        if (bitWidth < 16 || bitWidth > 512)
            throw new ArgumentException($"Bit Width {bitWidth} must be between 16 and 512.");
        _bitWidth = bitWidth;
    }
    public override int HashSize => _bitWidth;
    public override void Initialize()
    {
    }
    protected override void HashCore(byte[] bytes, int ibStart, int cbSize)
    {
        var buf = bytes.SubByte(ibStart, cbSize);
        HashValue = _hash.ComputeHash(buf).SubByte(0, _bitWidth >> 3);
    }
    protected override byte[] HashFinal()
    {
        return (byte[]) HashValue.Clone();
    }
}